Distiller grain production device

ABSTRACT

A device for producing a high density compact livestock feed from a loose granular material according to various embodiment can include a source for supplying a loose granular material to be treated and moving the treated material through a series of successive treatment zones. Rotatable screws are provided within an extruder to compress and transport the treated material a die. The treated material is pressed through the die while a two-dimensional cross-section compression is applied to the treated material.

FIELD OF THE INVENTION

This invention relates to an apparatus and method for treating granularmaterial such as dry distiller grains (DDG) for the purpose oftransforming the granular loose material into a dense cohesive bulkproduct and optionally extracting and collecting liquids and vapors fromthe bulk material as a separate product.

BACKGROUND OF THE INVENTION

In the field of animal feed processing, wet and dried distiller grainsare a major feed source for farm livestock. This is due in part to theincreased commercial interest in ethanol production. Wet distillergrains are one of the residual products of grain fermentation that formsduring the production of ethanol. This residue, which is sometimescalled mash, has relatively high water content in the range of about60-70% and has a high nutritional value, which is a good supplementalfood source for livestock.

However, one of the major problems with wet distiller grains is that itis susceptible to mold and mildew when exposed to air for about 4 to5days. This potential mold and mildew issue makes it imperative that thewet grains are used and consumed relatively quickly, because extendedstorage of wet grains is not feasible. To address the mold and mildewissues with wet grains, oftentimes, a drying process is applied to thewet grains prior to their delivery as livestock feed. Typically, the wetgrains are treated in rotating drying drums where combustion gases areheated to approximately 900 degrees Fahrenheit and then injected intothe wet grains to evaporate the excess moisture. At the conclusion ofthe drying process, the wet grains are transformed into dried distillergrains having moisture content in the range of 10 to 15% water. Thedried grains are a more desirable livestock feed in that they are not assusceptible to mold or mildew given their lower water content. Driedgrains therefore have longer storage life. The dried grains have anadded benefit in that they are more concentrated and therefore containmore nutritional value per unit volume than wet grains.

While dried grains have several advantages over wet grains, they do havesome properties that make them less than desirable as a livestock feed.First, the dried grains have a loose and granular consistency whichmakes them susceptible to dilution and spoilage when spread on theground as feed and exposed to the weather. In this loose granular form,the livestock consuming the dried grains do not receive the fullpotential benefit of the nutritional value of the feed, because of therelatively low density of the material. Second, transportation of loosegranular material such as dried grains also presents material handlingissues when compared to more dense bulk material. Another seriousconcern with dried grains is the safety of the drying process thattransforms wet grains to dried grains. Given that the drying processgenerally takes place in a rotating drum with an open boundary betweenthe grain and the heated combustion gases, there is a constant danger ofpotential explosions within the volatile atmosphere inside the dryingdrum. This problem can be a major safety hazard for personnel operatingthe dryers and it can cause down time and increased capital cost.

To address the low density concerns associated with the loose granulardried grains, pelletizing of dried grains has been implemented by manylivestock feed manufacturers. In some conventional methods, the pelletsor range cubes are formed by compressing dried grains with the additionof binder materials or supplements that help the resulting pellet becomedense and cohesive. While this solution is an improvement over the loosegranular dried grains, the addition of supplements to the dried grainsresults in an increase in cost and lowers the nutritional value per unitvolume of the final product in comparison to a dried grain pelletproduced without such binders and supplements. One of the main problemswith the pellets and cubes produced from this conventional technique isthat they are made with binders and fillers, to keep them together. Evenwith these additives, the pellets and cubes can fall apart. Thus, it maybe desirable to produce a cube or pellet having the highest protein andfat content, as naturally possible. A system and method is needed thatproduces a sufficiently dense pellet having the highest fat and proteincontent, without adding any binders, which are non-natural additiveslike molasses.

Some of the conventional pellet producing methods require a heating orcuring process applied to the pellet or cube after it is formed in orderto boil off the corn oil, which also lowers the protein level. Thus,there is a need to provide a method that does not require a heating orcuring process after the pellet or cube is produced.

After the pellet is made, it must be transported from the manufacturingfacility to the farmer. Typically, during transport, the product issubjected to several intermediate transfers using an auger. The cattlefeed industry currently produces cube and pellets that cannot be auguredseveral times. Even with the increase in product density, the resultingproduct that includes binders and supplements does not have sufficientdensity and cohesiveness to maintain their structural integrity whensubjected to the repeated stress of being augured several times duringtransport. This repeated stress can cause the product to break apart orbecome damaged. Thus, there is a need to produce a product that iscapable of being purchased in bulk, being transported via rail car orsemi-trailer load, being augured several times during transport, and,upon arrival at its destination, being augured by the existing feedingsystem that the cattle farmer already has installed.

SUMMARY OF THE INVENTION

The present invention may satisfy one or more of the above-mentioneddesirable features. Other features and/or aspects may become apparentfrom the description which follows.

It is the object of the invention to provide a livestock feed materialin the form of distiller dried grains without the addition of additivesand/or supplements by producing a pelletized livestock product that hashigh shipping durability, high quality, and high nutritional value.Thus, the final product provides optimum nutritional value in a verycompact and efficient form.

It is another object of the invention to extract and collect grain oilsand moisture from the distiller dried grains during the production ofpelletized distiller grain product.

It is another object of the invention to pass the distiller dried grainthrough a die that applies a cross-sectional compression. For example,some embodiments are directed towards a die that simultaneously appliesa two-dimension cross-sectional and lateral pressure at about 180degrees Fahrenheit, wherein the product exits the die 140 degrees.

It is a further object of the invention to produce, from distillergrain, a product such as a pellet or cube, which is sufficiently denseto endure being augured several times during transport without breakingapart and becoming damaged. The density of the pellets or cubes ismanipulated and controlled during the production process such itprevents the final product from crumbling or falling apart.

It is another object of the invention to provide a high-protein and fatproduct, without additives, that can be spread onto the ground aslivestock feed and is capable of enduring various weather conditions.

It is another object of the invention to provide a method, which doesnot require heating or curing of the pellets after the pellets areproduced.

It is another object of the invention to take an initial by-product ofan ethanol production or a corn by-product and produce a dried distillergrain product capable of being consumed by livestock.

In the following description, certain aspects and embodiments willbecome evident. It should be understood that the invention, in itsbroadest sense, could be practiced without having one or more featuresof these aspects and embodiments. It should be understood that theseaspects and embodiments are merely exemplary and explanatory and are notrestrictive of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The skilled artisan will understand that the drawings described beloware for illustrative purposes only. The drawings are not intended tolimit the scope of the present teachings in any way.

FIG. 1A shows a general schematic drawing of an exemplary embodiment ofa system for producing a distiller grain pellet in accordance with thepresent teachings;

FIG. 1B shows another exemplary embodiment of a system for producing adistiller grain pellet in accordance with the present teachings; medium;

FIG. 2 shows an example of a profile screw used to compress andtransport the distiller dried grains through the production line;

FIG. 3 shows a perspective view of a conical shaped compressionenclosure positioned between a first and second die where the distillerdried grains are simultaneously compressed parallel to the horizontalaxis of transport and then compressed transverse to the horizontal axisof transport;

FIG. 4 shows an alternative embodiment of FIG. 3 where the conicalshaped enclosure feeds multiple extrusion die extremity tubes;

FIG. 5 shows a compression enclosure where multiple distiller grain dieextremities have separately adjustable cooling heat exchangers for theindividual die extremities;

FIG. 6 shows a heat exchanger arrangement using a compressionrefrigeration system to cool the extruded distiller grain feed in thedie extremity;

FIG. 7A shows the collection and vacuum system that extracts andcollects oil from the extruded distiller grain exiting the cooling heatexchanger;

FIG. 7B shows an alternative embodiment of FIG. 7A where a cooling heatexchanger is mounted around a perforated die extremity;

FIG. 8 shows details of the perforated die extremity that permits oilwater and vapor to be vacuumed out of the treated distiller grain;

FIGS. 9A-9B show the device that adjusts the length of pellets exitingthe die extremity; and

FIG. 10 illustrates an operational flow chart of a method of producingdistiller grain pellets utilizing the device in accordance with thepresent teachings.

DESCRIPTION OF THE EMBODIMENTS

Reference will now be made to various embodiments, examples of which areillustrated in the accompanying drawings. However, these variousexemplary embodiments are not intended to limit the disclosure. On thecontrary, the disclosure is intended to cover alternatives,modifications, and equivalents.

Throughout the application, description of various embodiments may use“comprising” language, however, it will be understood by one of skill inthe art, that in some specific instances, an embodiment canalternatively be described using the language “consisting essentiallyof” or “consisting of.”

For purposes of better understanding the present teachings and in no waylimiting the scope of the teachings, it will be clear to one of skill inthe art that the use of the singular includes the plural unlessspecifically stated otherwise. Therefore, the terms “a,” “an” and “atleast one” are used interchangeably in this application.

Unless otherwise indicated, all numbers expressing quantities,percentages or proportions, and other numerical values used in thespecification and claims, are to be understood as being modified in allinstances by the term “about” or “approximately.” Accordingly, unlessindicated to the contrary, the numerical parameters set forth in thefollowing specification and attached claims are approximations that mayvary depending upon the desired properties sought to be obtained. Insome instances, “about” or “approximately” can be understood to mean agiven value ±5%. Therefore, for example, about 100 degrees Fahrenheitcould mean 95-105 degrees Fahrenheit.

Various embodiments of the distiller grain pellet producing devicesdescribed herein enable pellet production without the addition ofbinders and fillers to avoid negatively affecting the nutritional valueof the final product. Various embodiments of the distiller grain pelletproducing devices produces a livestock feed material in the form ofpelletized distiller dried grains having high shipping durability, highquality, and high nutritional value. The final product provides optimumnutritional value in a very compact and efficient form. Variousembodiments extract and collect grain oils and moisture from thedistiller dried grains during the production process. Variousembodiments of the pellet producing device pass the distiller driedgrain through a die that applies a cross-sectional compression, whilecontrolling the density of the product. Various embodiments of thepellet producing device in various structural forms, for example, in theform of pellets, cubes, or tubs having various configurations such asround, square, rectangular or oblong.

Various embodiments of the pellet producing device provides ahigh-protein and fat content product, without additives, that can bespread onto the ground as livestock feed and is capable of enduringvarious weather conditions. Various embodiments provide a method thatdoes not require heating or curing of the pellets after the pellets areproduced. Various embodiments of the pellet producing device take aninitial by-product of an ethanol production or a corn by-product andproduce a dried distiller grain product capable of being consumed bylivestock.

FIG. 1A shows a schematic diagram of a distiller grain (DG) pelletproduction device 100 which can be used to process dried distillergrains into pelletized distiller grain product. The pellet productiondevice 100 can include a loading zone, which may include a hopper 101, aheating zone, which may include heaters 105, a compression zone, whichmay include a compression enclosure 110, and a cooling zone, which mayinclude a heat exchanger 117. The device 100 can include a loading zonefor loading the distiller dried grains into the heating zone. Distillerdried grains supplied from hopper 101 in loose granular form can be feedinto the heating zone at an inlet chute 102 of a profile screw extruder112 shown in FIGS. 1A and 2. A variable speed motor 104 connects to thescrew of the extruder and drives the screw element 103 of the profilescrew extruder.

The distiller dried grains entering the profile screw extruder at inletchute 102 can have a moisture content in the range of about 10-15% byweight. As the distiller dried grain is conveyed and compressed withinthe profile screw extruder 112, heat is added to the distiller driedgrain by heaters 105 positioned along the wall 106 of the profile screwextruder. FIG. 2 shows a general shape of the profile screw 112 wherethe shaft diameter increases from d1 to d2 along the length of the screwwhich creates an increasing compression force on the treated materialbeing conveyed downward due to the rotation of the screw. The heaters105 can be arranged along the profile screw 112 in heating zones wherethe individual heaters can be equipped with independent heater controlsfor creating separate heating zones where selected temperatures aremaintained in the treated distiller grain as it is conveyed andcompressed in the profile extruder 112. The type of heater devicesemployed for heating the treated material can include but are notlimited to electric heaters, combustion gas heaters, microwave heaters,solar powered heaters or any combination of these or any other suitableheating devices.

A series of temperature sensors, for example, T1, T2, T3, T4 and T5, maybe embedded within the wall 106 of the profile screw extruder. Thesetemperature sensors can be used to monitor the temperature of thetreated material so that appropriate adjustments to the heater output,distiller died grain feeding rate, and profile screw rotation rate areregulated to maintain the treated material within a desired temperaturerange along the treatment zones of the profile screw extruder 112. Whilefive temperature sensors are shown, it should be understood that theremay be more temperature sensors or less temperature sensors depending onthe material treated, the length of the profile screw extruder and thedesired precision of temperature monitoring within the heating andcompression treatment zone. It should be noted that the temperaturesensors may be connected in a computer control loop where the individualheater output regulators, a profile screw extruder motor speedregulator, and a distiller grain feed flow controller may all beindividually controlled by a controller 10 to maintain preselectedtemperature conditions in the treated distiller grain as it travelsalong the profile screw extruder 112.

In some embodiments, the heating zone may include a plurality ofadjacent treatment zones. In some embodiments, the heating zone mayinclude adjacent treatment zones where no heat is applied to the treatedmaterial. In other embodiments, the heating zone may consist of a singletreatment zone. Control of the motor 4 regulates the residence time ofthe treated material in the treatment zones.

In the heating zone, the process is monitored and controlled to cause amixture of liquid and vapor from the water and oils contained in thedistiller grain to begin to boil such that the distiller grain becomesmodulus. The modulus state of the distiller grain enables it to betterflow the restrictive passage(s) provided in the compression zone.

FIG. 3 shows a conical shaped compression enclosure 110 in thecompression zone in which the heated distiller grain enters as it exitsfrom an outlet 111 of profile screw extruder 112 in the heating zone.The compression enclosure 110 can have a variety of configurations(e.g., size, shape, etc.) such that, for example, passing a treatedmaterial through the enclosure 110 generates sufficient compressiveforces on the treated material to form a dense compact material. Forexample, the compression enclosure may be a restrictive die 110 as shownin the figures. In various embodiments, the pellet production device 100can be designed to be material specific such that the configuration ofthe compression enclosure 110 (e.g., the configuration of one or moredie through holes) can be selected based upon the compression raterequired for the treated material selected for pelletizing.

As shown in the figures, initially, the distiller grain is forcedthrough a first die orifice 107 located at the entrance of die 110 bythe pressure applied to the treated material due to the rotation of theprofile extruder 112. This first die orifice 107 generally has a crosssection area that is less than the cross sectional area defined by thecircumference of the inside wall 108 of the outlet 111 of the profileextruder shown in FIG. 2. The configuration of the die 110 performs acritical function in the process to form the treated distiller grain.The die 110 is configured such that the distiller grain is compressedparallel to its axis of transport and it is also compressed in adirection transverse to the direction of transport as it passes through.A simulated free body diagram of the compressive forces on the treatedmaterial at location 114 inside the enclosure is shown in FIG. 3 whereT_(F) represents the transverse compression force and H_(F) representsthe force acting parallel to the axis of material transport. Thistransverse compression T_(F) of the treated distiller dried grainstrengthens the outer surface of the treated distiller grain whichresults in a more durable final product. The amount of transversecompression T_(F) that is applied to the distiller dried grain incompression enclosure 110 depends on the pressure applied by the profileextruder 112, the length of enclosure 110 and the angle of inclination Aof the surface walls. These parameters can be selected to design aspecific compression enclosure 110 to obtain a desired outer surfacedurability of the final product and the type of material that is beingtreated. In this example, the compression enclosure is shown as a diehaving a conical shaped configuration. In this example, the compressionenclosure is shown as a die having a conical shaped configuration.

Ideally, the transverse compression force T_(F) and the parallel forceH_(F) are approximately equal for most, but not all applications.Several sensors can be employed to assist in monitoring the condition ofthe distiller grain as it passes through the compression enclosure 110.For example, using temperature sensor T5, the temperature of the treateddistiller grain can be measured prior to entering the first die orifice107. A further distiller dried grain temperature reading can be measuredbetween the first die orifice 107 and the second die orifice 115 bytemperature sensor T7. Another temperature reading can be taken attemperature sensor T8 to measure the temperature of the treateddistiller grain after it passes the second die orifice 115 and exits thedie extremity tube 116.

Due to the process of creating pressure in the compression enclosure110, the moisture (mainly corn oil) in the distiller grain is forced tothe outside walls of the extrudate after exiting the second die orifice115. Thus, the mixture of heated liquid and vapor from the oil and waterin the distiller grain migrates to and collects on the outer surfaces ofthe treated distiller grain to form a lubrication layer. The oilfunctions as a lubricant between outer surface of the distiller grainand the inner wall of the die extremity tube 116 and helps the distillergrain to pass through the die extremity. The treated distiller grain isstill in a relatively modulus state when it is directed into a dieextremity tube 116. The modulus state of the treated material enables itto easily deform elastically and conform to the shape of the dieextremity tube 116. The diameter and shape of the die extremity tube 116can be selected according to the desired shape and size of the finalproduct. In some embodiments, the compression enclosure 110 may includea plurality of die extremity tubes 116, as shown in FIGS. 4 and 5. Forexample, the die extremity tubes 116 may have a cross section openingthat will produce a round, square, rectangular or oblong shape to namejust a few of the possible configurations. FIG. 4 shows a modifiedcompression enclosure 110 a with multiple die openings 115. FIG. 5 showsdifferent die extremity tubes 116 having different diameter and shapeextending from the modified compression enclosure 110 b. Some examplesof the different kinds of cross sections may include round, square,rectangular, star shaped, triangular etc. It should be understood thatthe cross-sections of the die extremity tubes 116 depicted in thefigures are exemplary only and those having ordinary skill in the artwould appreciate that a variety of geometric structures having differingconfigurations and numbers may be substituted for or used in conjunctionwith the die extremity tubes 116. The plurality of die extremity tubes116 may include geometric structures of the same or differingconfigurations.

As the treated distiller grain is pushed through the die extremity tubes116, the distiller grain may be cooled in a heat exchanger assembly 117.In FIG. 1A, the heat exchanger assembly may use water as its coolingagent and the cooling water enters or exits the heat exchanger 117 byway of pipes 118 and 119. Either of pipes 118 or 119 can be used as theentry point or exit point of the cooling water depending on the type offlow that is desired in the heat exchanger. In FIG. 1B the heatexchanger 117 is cooled by a cooling medium processing device 120. Thecooling medium processor 120 can be in the form of any known coolingsystem. A partial listing of cooling devices and methods that may beused would include cryogenic coolers, refrigerated air heat exchangers,water chillers, cooling towers and any other known cooling device orcombination of cooling devices that are capable of cooling the treateddistiller grain to a stable internal temperature before it is dischargesas a final product. Another exemplary cooling system for multiple dieextremity tubes is shown in FIG. 5. In this arrangement two differentshaped die extremity tubes 116 a and 116 b are cooled in heat exchangers117 a and 117 b. The control of the flow of the coolant to the heatexchangers 117 a, 117 b is regulated by control valves 125 a and 125 b.Valve control regulators 126 a and 126 b can be set to maintaindifferent cooling rates in heat exchangers 117 a and 117 b. The valvecontrol regulators 126 a and 126 b could also be functionally connectedto temperature sensors 128 a and 128 b located in the heat exchangers117 a or 117 b or in the die extremity tubes 116 a or 116 b to controlthe flow of coolant through valves 125 a and 125 b to maintain a desiredtemperature in the heat exchanger, the die extremity tubes or treateddistiller grain.

Another exemplary embodiment of a cooling arrangement is shown in FIG.6. In this arrangement, two vapor compression refrigeration systems areused to cool the treated distiller grain in the die extremity tubes.Refrigeration compressors 121 a and 121 b direct compressed refrigerantvapor to condensers 122 a and 122 b. The condensed refrigerant is thanpassed through expansion valves 123 a and 123 b where low pressure coolrefrigerant is then passed into heat exchangers coils 117 a and 117 b.The evaporated refrigerant gas exiting heat exchangers coils 117 a and117 b is then passed back to the suction side of compressors 121 a and121 b by way of lines 124 a and 124 b. The refrigeration systems of FIG.6 can be regulated by well-known refrigeration control devices. While adual compression refrigeration system is disclosed as the cooling meansfor the treated distiller grain in FIG. 6 a single compressionrefrigeration cycle system could also be used to provide coolingrefrigerant to a single cooling coil.

The cooling process has a significant impact on the physical propertiesof the final product. The amount of cooling is regulated to ideallyproduce a stable and cohesive final product which is discharged from thedie extremity tubes 116. If insufficient cooling is applied during thecooling process, then the product exiting the die extremity tubes maypossibly explode or over expand due to excessive pressure inside of thetreated distiller grain. In certain situations as illustrated in FIG. 5,it may be necessary to apply different cooling rates to die extremitytubes 116 a and 116 b extending from the same compression enclosure 110b when the size and shape of the die extremity tubes are different or toproduce two or more different final products having differentproperties. If excessive cooling is applied during the cooling process,this could result in an increase in friction between the die extremityinner wall and the treated distiller dried grain. As a result, this mayincrease the power required to push the finished product out of the dieextremity tube. In the worst case scenario, the treated distiller driedgrain may become lodged in the extruder die tube 116.

FIG. 7A shows an optional water/vapor and oil extraction and recoverysystem. In this arrangement, the extraction system is deployed at theend of the die extremity tube 116. The distiller grain exiting the dieextremity tube 116 enters a perforated pipe 129 having perforations 130that are arranged in slots around the lower portion of pipe 129.Perforations 131 are provided in the upper portion of pipe 129. Pipe 129is surrounded by a tube 132 that includes a collection pipe 133 which inturn is connected to separating vessel 134. FIG. 8 shows further detailsof the perforations 130 and 131 in pipe 129. A pipe 135 is connected tothe inlet of a vacuum pump 136 which discharges into pipe 162. When thevacuum pump is operated, a vacuum is created in the space between theinner wall of tube 132 and the openings 130 and 131 in the perforatedpipe that are exposed to the surface treated distiller dried graininside pipe 129. The vacuum acts to extract oil, water and/or vapor fromthe surface and the interior of the treated distiller grain through theopenings 30, 31 as the treated material passes through inside pipe 129.The collected oil, water and/or vapor are then directed to the separatortank 134 by way of pipe 133. The separation tank 134 directs thecollected oil, water and/or vapor through a path that separates the oilfrom the water within the separator tank. The oil is then drawn out ofthe separation tank to be used on site or to be shipped out to beprocessed into other products such as diesel fuel. The water may becollected and used on site or it may be discharged out of pipe 147.

An alternative embodiment of a water/vapor and oil extraction system isshown in FIG. 7B. This embodiment permits the possible application oftwo different cooling sources in the cooling process for the treateddistiller grain. After the treated distiller grain is cooled in apreliminary heat exchanger 117, the treated distiller grain is directedto an additional heat exchanger arrangement in the form of a coil 144that is wrapped around a perforated pipe 129 having perforations 130 and131. The first heat exchanger 117 may be cooled, for example, by waterand the second heat exchanger cooled by a compression vaporrefrigeration system similar to that shown in FIG. 6. Other coolingsources may be applied to either heat exchanger 117 and 144 as desired.The heat exchanger 144 includes coolant inlets and outlets 145 and 146.The inlets and outlets 144 and 145 are interchangeable depending on thetype of coolant flow desired. The perforations 130 and 131 are locatedbetween the coils 44 that form the heat exchanger. A tube 132 enclosesthe heat exchanger 144 and the perforated pipe 129. The perforations 130and 131 are spaced such that they are not covered or obstructed by theheat exchanger coils 144. The space between the inside wall of pipe 132and the perforations 130 and 131 in pipe 129 are subjected to a vacuumby way of pipe 133 that is connected to separating tank 134 and vacuumpump 136. In this particular embodiment, the vacuum created inside pipe132 tends to draw the treated distiller dried grain against the insidewall of perforated pipe 129 to provide better heat transfer between thetreated distiller grain and heat exchanger coils 144. If the treateddistiller grain exiting the second die 115 in the compression enclosure110 is sufficiently stable, the treated distiller grain may be simplypushed through the first heat exchanger 117 and the cooling process maybe implemented in the second heat exchanger 144.

FIG. 9A shows a cutting device 137 that may be used after the coolingprocess to cut the treated material into pellets having a desiredlength. The pellets may also be referred to as range cubes. The cuttingdevice 137 includes a mounting bar 138 a lateral adjustment clamp 139that is connected to a connecting rod 40 which is pivotally connected atpivot 143 to the pellet length adjustment member 142. A locking bolt 150screws into the top of clamp 139 to secure the lateral position of theconnecting rod 140 on the support bar 138. The pivot point 143 shown inFIG. 9B comprises two spaced apart members 151 and 152 that receiveconnecting rod 140. Members 151, 152 and 140 are secured in a pivotingrelationship by bolt 149 and lock nut 148. The pivot 143 may be in theform of a ball and socket or any other device that will permitadjustable pivotal motion between the connecting rod 140 and pelletlength adjustment member 142. The support bar 138 can be mounted on theend of the die extremity tube 116 or other support member. In FIGS. 1,7A, and 7B, this cutting device 137 is positioned above the exit pointof device 100 such that it cuts the treated material into pellets, whichmay be collected into a container 160. By adjusting the lateral positionof the pellet length adjuster 142 along the support bar 138 and alsoadjusting the angle of inclination of the pellet length adjuster 142 atpivot point 143, element 142 can be arranged to exert a selected degreeof downward force on the treated distiller grain exiting the dieextremity tube 116 which determines the length of the resulting pellets113.

In general, the present teaching relates to an apparatus and method oftaking wet and dry distiller grains and articles alike and feeding theminto an extruder, which may be configured having a continuous screw andbarrel arrangement 106. The distiller grains and articles alike areconveyed through the screw of the extruder while the screw and barrelare heated in zones to prescribed temperatures which brings thedistiller grain moisture (water and corn oil) close to a boiling pointwhere the distiller grains become modulus to the point where it willflow through a restrictive die 110 that substantially reduces theorifice size. Pressing the grain as it flows through the restrictive diecreates substantial pressure (2,000 to 10,000 PSI) between the tip ofthe screw(s) of the extruder and the restriction of the orifice in thedie. The pressure created by the restriction of the die makes thedistiller grains pack densely in the die. The greater the differencebetween the first die orifice 107 and the second die orifice 115, thegreater the pressure created upon the distiller grain and thus thegreater the density of the distiller grain extrudate will be.

During this process of creating pressure, the moisture (mainly corn oil)is forced to the outside walls of the extrudate after it has left thesecond die orifice 115. The oil allows the product to function as alubricant between the outside wall of the extrudate and the inner wallof the die extremity 116 which will form the shape of the finalextrudate desired. This lubrication helps the extrudate pass through thedie extremity. The longer the length of the die extremity (land time) isthe more drag it creates upon the extrudate and also increases thepressure between the first die orifice 107 and the second die orifice115. The die extremity is quite lengthy because the extrudate needs tobe cooled well below the boiling temperature of water and corn oilcombined under pressure (about +140 F). This is done by creating coolingpassage ways or circuits that are located around the die extremitycreating a heat exchange coil. Liquid and gas refrigerants are passedthrough the heat exchanger in a closed loop fashion with the assistanceof a refrigeration compressor. A temperature controller where the liquidand gas refrigerants are cooling the die extremity and the die extremitycools the extrudate via conductive heat transfer.

A vacuum may need to be created and pulled from the inside of the dieextremity via vacuum slots 130, 131. Using, for example, a continuousvacuum pump, the vacuum is created to constantly pull the externalsurface of the extrudate against the internal walls of the die extremityto create effective wall contact in order for conductive heat transferto occur. If effective cooling does not occur before the extrudateleaves the die extremity, then the extrudate may simply split openrelieving the boiling gas of the water and corn oil mixture and damagingthe integrity and size and shape and density of the extrudate. In someembodiments, as shown in FIGS. 4-5, multiple die extremities 116, 116 a,116 b may be included on the same die to allow for high volume output ofextrudate but still allowing a slow speed within each die extremity forlonger dwell time to achieve adequate cooling. The examples in FIGS. 4-5show only two to three multiple die extremities extending from a singledie, but the design is not limited to this exemplary embodiment. Thedevice has been designed and manufactured to include, for example,fifteen to twenty die extremities extending from a single die.

FIG. 10 illustrates an operational flow chart of a method for producingthe distiller grain pellets utilizing the device in accordance with thepresent teachings. Dried corn distiller grain with a moisture content ofabout 10-12% by weight is feed into hopper at block 200. The dried corndistiller grain is passed into a heating zone comprising one or moreheaters and a rotating screw as indicated in block 210. The dried corndistiller grain is gradually heated in by electrical heaters, forexample, in five heating zones where the dried corn distiller grain isheated to about 140 degrees Fahrenheit by the time it arrives at thelocation designated as T5. Rotation of the screw transfers the driedcorn distiller grain through the heating zone while simultaneouslyincreasing the compressive force applied to the distiller grain asindicated at block 220. At this point oil and water in the treated corndistiller begins to boil. The distiller grain becomes modulus such thatit is capable of flowing through a restrictive die. The dried corndistiller grain is transferred into a compression enclosure thatsimultaneously applies a transverse force and a parallel force onto thedistiller grain as indicated at block 230. The dried corn distillergrain is pressed through the first die orifice 107. As the dried corndistiller grain is compressed and conveyed to the second die orifice 115near a location designated as T6, its temperature has increased toapproximately 180-200 degrees Fahrenheit. Controlling the density of thetreated material, the dried corn distiller grain begins to transforminto a cohesive dense elastic material and the oil migrates toward theouter surface of the distiller grain at the second die orifice. With theoil and water acting as a lubricating agent to assist in pressing thematerial through the second orifice 115, for example, having a ¾ inchdiameter, the material is passed through to one or more die extremitieswhere a cooling process is then applied to the distiller grain asindicated at block 240. In the cooling zone, the distiller grain entersa water cooled heat exchange 116 where it is cooled to an internaltemperature of less than 140 degrees Fahrenheit at a location designatedas T8 before exiting as a dense durable and stable product, without theaddition of binders and fillers. Optionally, oils, water, and vapors canbe extracted from the distiller grain as it exits the cooling zone asindicated at block 250. The distiller grain can now be cut intonutritional pellets or cubes having a desired length or shape asindicated at block 260 and discharged from the device into a containeras indicated at block 270.

In various embodiments, in addition to producing pellets/cubes, device100 may be employed to produce a final product shaped as large tubshaving distiller grains compressed therein. The farmers can put out thetubs and not have to feed pellets/cubes to the livestock every day. Thetubs may weigh approximately 200 pounds and the density of the tubslimits the intake of the supplement to roughly 2-pounds of product perday, which allows the livestock eating the product to meet their dailyrequirements.

It will be apparent to those skilled in the art that variousmodifications and variations can be made to the pellet producing deviceand method of the present disclosure without departing from the scope ofits teachings. In various embodiments, a wide variety of different kindsof pellets, cubes or tubs can be produced from various loose granularmaterials using substantially the same device since virtually unlimitednumbers of shapes of the compression enclosure and one or more dieextremity tubes can be designed and used to meet the requirements of aparticular loose granular material. For example, the device may be usedto compress feeding products such sorghum.

It should be noted that various embodiment of the device includes acontroller 10 that controls various sensors and components, such aspressure sensors, humidity sensors, temperature sensors, and drivecontrols, positioned in various locations throughout the device andconnected in a computer control loop to set, maintain and controlpreselected conditions such as temperature, pressure, humidity, density,flow rate, and residence time in the treated material and/or componentsof the system.

Other embodiments of the disclosure will be apparent to those skilled inthe art from consideration of the specification and practice of theinvention disclosed herein. It is intended that the specification andexamples be considered as exemplary only.

What is claimed is:
 1. A device for producing a high density compactlivestock feed from a loose granular material, comprising: a source forsupplying a loose granular material to be treated; a controller incommunications with a plurality of sensors for monitoring temperature ofat least one zone as the treated material moves through a series ofsuccessive treatment zones; an extruder comprising an elongated housinghaving an inlet end and a discharge end, the inlet end in communicationwith the source and to receive the loose granular material to be treatedand to compress the treated material within the extruder, wherein theextruder includes: rotatable screws provided within the housing andextending between the inlet end and the discharge end for compressingand transporting the treated material, the screws configured to apply anincreasing compressive force to the treated material as the screwsrotate and move the treated material longitudinally along the screws; atleast one drive coupled to the screws for axially rotating the screws;at least one heater disposed along a portion of the housing for heatingthe treated material moving along the screws to a first predeterminedtemperature which causes at least one of an oil and a liquid to boilwithin the treated material and changes physical properties of thetreated material into a modulus state; at least one treatment zoneprovided within the extruder, wherein the at one treatment zonecomprises at least one non-heating zone provided in the housing suchthat no heating is applied to the treated material; and a die located attips of the screws at the discharge end of the extruder for creating asubstantial pressure for compacting the treated material, wherein thedie includes: a chamber having a through hole which extendslongitudinally through the chamber and provides a restricted passagewayfor compressing the treated material, the through hole includes an inletorifice for receiving the treated material from the discharge end of theextruder and an outlet orifice for discharging the treated material,pressing the treated material in the modulus state longitudinallythrough the restricted passageway by applying a two-dimensionalcross-section compression which includes a pressure applied in adirection traverse to a direction of transport and a pressure applied ina direction parallel to the direction of transport, the two-dimensionalcross-section compression is applied to the treated material such thatliquids in the treated material migrates to its outer surface uponreaching the outlet orifice.
 2. The device of claim 1, wherein the highdensity compact body is shaped to form at least one of a pellet, a cubeand a tub.
 3. The device of claim 1, wherein, in the chamber, thepressure applied in the traverse direction onto the treated material issubstantially equal to the pressure applied in the parallel direction.